Method and apparatus for video encoding and decoding using bi-prediction

Abstract

Different implementations are described, particularly implementations for video encoding and decoding using motion compensation with bi-prediction are presented. The encoding method comprises for a picture, obtaining a first predictor for a block of the picture using a first reference picture; obtaining a second predictor for said block of the picture using a second reference picture; using the first predictor and the second predictor for forming a third predictor for the block in bi-prediction inter prediction, wherein the third predictor is obtained as a weighted average of the first predictor and the second predictor; and wherein a weight used in the weighed prediction depend on the position of the sample in the block. Others embodiments are presented for implementing block triangle partition prediction, for implementing block partition prediction using multiple patterns and for corresponding motion compensation in decoding method.

The invention claimed is: 
     
       1. A method, comprising:
 obtaining a first information indicating a splitting of a block of a picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 decoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       2. The method of  claim 1 , wherein the first weight and the second weight are in a range [0-8] and wherein the bit depth of the weighted average is larger than or equal to the processing bit depth plus 5. 
     
     
       3. The method of  claim 1 , wherein the first weight and the second weight depend on a distance between the sample and an edge of the geometric partition of the block. 
     
     
       4. The method of  claim 1 , wherein the block of the picture comprises a luma component and two chroma components and wherein the first weight and the second weight further depend on the luma component or chroma component. 
     
     
       5. An apparatus, comprising:
 one or more processors, wherein the one or more processors are configured to:
 obtain a first information indicating a splitting of a block of a picture with a geometric partition; 
 obtain, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtain, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtain a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtain a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 decode the block of the picture using the third predictor generated by a geometric partition mode. 
 
 
     
     
       6. The apparatus of  claim 5 , wherein the first weight and the second weight are in a range [0-8] and wherein the bit depth of the weighted average is larger than or equal to the processing bit depth plus 5. 
     
     
       7. The apparatus of  claim 5 , wherein the first weight and the second weight depend on a distance between the sample and an edge of the geometric partition of the block. 
     
     
       8. The apparatus of  claim 5 , wherein the block of the picture comprises a luma component and two chroma components and wherein the first weight and the second weight further depend on the luma component or chroma component. 
     
     
       9. A method, comprising:
 obtaining a first information indicating a splitting of a block of a picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       10. The method of  claim 9 , wherein the first weight and the second weight are in a range [0-8] and wherein the bit depth of the weighted average is larger than or equal to the processing bit depth plus 5. 
     
     
       11. The method of  claim 9 , wherein the first weight and the second weight depend on a distance between the sample and an edge of the geometric partition of the block. 
     
     
       12. The method of  claim 9 , wherein the block of the picture comprises a luma component and two chroma components and wherein the first weight and the second weight further depend on the luma component or chroma component. 
     
     
       13. An apparatus, comprising:
 one or more processors, wherein the one or more processors are configured to:
 obtain a first information indicating a splitting of a block of a picture with a geometric partition; 
 obtain, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtain, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtain a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtain a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encode the block of the picture using the third predictor generated by a geometric partition mode. 
 
 
     
     
       14. The apparatus of  claim 13 , wherein the first weight and the second weight are in a range [0-8] and wherein the bit depth of the weighted average is larger than or equal to the processing bit depth plus 5. 
     
     
       15. The apparatus of  claim 13 , wherein the first weight and the second weight depend on a distance between the sample and an edge of the geometric partition of the block. 
     
     
       16. The apparatus of  claim 13 , wherein the block of the picture comprises a luma component and two chroma components and wherein the first weight and the second weight further depend on the luma component or chroma component. 
     
     
       17. A non-transitory computer readable medium containing encoded data representative of a block of a picture of a video, the encoded data being formed by performing:
 obtaining a first information indicating a splitting of the block of the picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       18. A non-transitory program storage device, readable by a computer, tangibly embodying a program of instructions executable by the computer for performing the method according to  claim 1 . 
     
     
       19. A method for transmitting encoded data representative of a block of a picture of a video, the method comprising transmitting encoded data formed by:
 obtaining a first information indicating a splitting of the block of the picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       20. An apparatus for transmitting encoded data representative of a block of a picture of a video comprising a memory and one or more processors configured to transmit encoded data formed by:
 obtaining a first information indicating a splitting of the block of the picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       21. A method for receiving encoded data representative of a block of a picture of a video, the method comprising receiving encoded data formed by:
 obtaining a first information indicating a splitting of the block of the picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than the processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       22. An apparatus for receiving encoded data representative of a block of a picture of a video comprising a memory and one or more processors configured to receive encoded data formed by:
 obtaining a first information indicating a splitting of the block of the picture with a geometric partition; 
 obtaining, from uni-prediction, a first predictor for the block of the picture using a first reference picture, wherein a bit depth of the first predictor after uni-prediction is larger than a processing bit depth; 
 obtaining, from uni-prediction, a second predictor for the block of the picture using a second reference picture, wherein a bit depth of the second predictor after uni-prediction is larger than a processing bit depth; 
 obtaining a weighted average of the first predictor and the second predictor; 
 wherein a sample of the weighted average is obtained by applying a first weight to a sample of the first predictor and by applying a second weight to a co-located sample of the second predictor, wherein the first weight and the second weight are responsive to the first information and wherein a bit depth of the weighted average is larger than the processing bit depth; 
 obtaining a third predictor for the block by shifting and clipping the weighted average to the processing bit depth wherein the shifting compensates for the bit depth increase of both the weighted average and the uni-prediction of the first and second predictors; and 
 encoding the block of the picture using the third predictor generated by a geometric partition mode. 
 
     
     
       23. The method of  claim 1 , wherein the first weight and the second weight are in a range [0-8] and wherein the shifting to the processing bit depth is larger than or equal to 5. 
     
     
       24. The apparatus of  claim 5 , wherein the first weight and the second weight are in a range [0-8] and wherein the shifting to the processing bit depth is larger than or equal to 5. 
     
     
       25. The method of  claim 9 , wherein the first weight and the second weight are in a range [0-8] and wherein the shifting to the processing bit depth is larger than or equal to 5. 
     
     
       26. The apparatus of  claim 13 , wherein the first weight and the second weight are in a range [0-8] and wherein the shifting to the processing bit depth is larger than or equal to 5.